US3728237A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing aluminum electrode foil for electrolytic capacitors
Assignee: US Philips Corp
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Filing: 1971-07-16
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Granted: 1973-04-17
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Expires: 1991-07-16
Abstract
Abstract IMPROVEMENT IN ETCHING OF ALUMINUM FOIL FOR ELECTROLYTIC CAPACITORS WHEREIN AMMONIUM PERSULFATE, TARTARICACID OR A SOLUBLE TARTRATE IS ADDED TO THE ETCHING SOLUTION.
Inventors
- 👤 M Heijenbrok
- 👤 Herwijnen A Van
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:27
CPC Classifications
H; H01; H01G; H01G9/00; H01G9/004; H01G9/04; H01G9/048; H01G9/055; C; C22; C22F; C22F1/00; C22F1/04; C25; C25F; C25F3/00; C25F3/02; C25F3/04; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12431
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |